Nasal drug delivery has received a great deal of attention as a convenient, reliable, and promising method for the systemic administration of drugs. The use of the nasal route for the delivery of challenging drugs such as small polar molecules, vaccines, hormones, peptides and proteins has created much interest in nowadays.
It is especially for those molecules which are ineffective orally and only effective if administered by injection.
Due to the high permeability, high vasculature, low enzymatic environment of nasal cavity and avoidance of hepatic first pass metabolism are well suitable for systemic delivery of drug molecule via nose. Many drug delivery devices for nasal application of liquid, semisolid and solid formulation are investigated to deliver the drugs to the treat most crisis CNS diseases (i.e., Parkinson’s disease, Alzheimer’s disease) because it requires rapid and/or specific targeting of drugs to the brain.
This review sets out to discuss some factors affecting nasal absorption, bio-availability barriers, strategies to improve nasal absorption, new developments in nasal dosage form design and applications of nasal drug delivery system.